Miniaturized laboratory is a technological progress in biology and chemistry in recent years. Droplet microfluidics provides the miniaturizing technique to manipulate defined samples and reagents in microscale droplets. Stable and highly monodisperse droplets in the picoliter to nanoliter volume range can be generated on microfluidic platform and integrated to “Lab-on-a-chip” systems. Through transportation, fusion, split, sorting, samples and reagents confined in microdroplets can be sampled, analyzed, and with reaction occurred inside.
Microdroplets as naturally well-defined microreactors greatly prevent sample loss, cross-contamination, and concentration change due to diffusion. Owing to the high surface to volume ratio, microdroplets are granted with fast thermal transfer, fast and efficient mixing. At the same time the microdroplets are so tiny and able to be produced in a very fast rate which led their great applications in high throughput screening technology. With those unique advantages, microdroplets and droplet-based microfluidics have offered new routes to chemical and biochemical analysis, chemical and biochemical synthesis, chemical reactions, and material synthesis.
However, the existing microfluidic devices do not allow on-demand droplet manipulations integrated into it. Such on-demand droplet manipulations on single microfluidic platform allow the conduction of droplet based reactions with real time monitoring and also further analysis. On-demand methods also provide the selectivity of when to start the reactions and in a certain way, what reagents/particles to be involved in the reaction, what concentrations of reagents to be introduced.
It is therefore an object of the present invention to provide an improved microfluidic device which allows at least a partly droplet manipulation.